Electric heater



March 7, 1933. L T, BENNETT 1,899,933

ELECTRIC HEATER Original Filed Jan. 30. 1928 2 Sheets-Sheet l INI/ENTOR ."1 ffmc/wy nay awt,

` March 7, 1933. 1. Tl BENNETT ELECTRIC HEATER 2 vSheets-Sl'leet 2 Original Filed Jan. 30. 1928 z/Jjf N VEA/TOR [Pw/VG MEA/NETZ m A TTORNEY Patented Mar. 7, 1933 ll'JurrED STATES Param'-y oli-luca IRVING T. BENNETT, OF BROOKLYN, NEW YORK, ASSIGNOR TO THOMAS E. MURRAY, 0F BROOKLYN, NEW YORK.; JOSEPH BRADLEY MURRAY, THOMAS E. MURRAY, JR., .AND JOHN F. MURRAY EXECUTORS SAID THOMAS E. MURRAY, DECEASED' ELECTRIC HEATER Original application filed January 3D, 1928,.Seria1 No. 250,350. Patent No. 1,796,317, dated March 17, 193.1.

Divided and this application filed April 25, 1928.

- The present application is a Vdivision of an application filed January 30, 1928, Serial No. 250,350, for improvements in radiators, and is directed totheelectric heating element alone or in connection with other apparatus.

`The accompanyingfdrawings illustrate an embodiment ofthe invention.-

Fig. 1 is a sideelevation, partly broken away, of a complete yheater;.

Fig. 2 is a separate view in perspective of aninsulating block; f

Fig. 3 is a horizontal section through. the heater at the level of onelength ofthe heating element y(I II III, Fig..-5).; I.:

Fig.-, 4 is a horizontaly section through the middle of the heater,(IV-IV, Fi g.5) f;y

Figs. 5, 6 and .7 are respectively/'sections on the lines 5,1-5; 6-,6 and 7 7 ofFig. 4;

Fig. 8 is a separate view of part of the electric resistanceelement. i' .l y

Figs. 9, 10 and 11 arerespe tively alplan and side and end views ofa modi'cation;

. Figs.- 12 and 13 are-views .corresponding to views 2 and 4 also .illustrating a modiiication.

The heating ,element comprises a loop.. of coiled resistance wire. 1 extending. in gt'wo lengths-from' end jto end andl p assinggout throughan insulator 2. (Fig.1) to-'circuit wiresl* and 1". The coil is enclosed directly between insulating blocks 3 carried in, a tubular casing 401?` oblong cross-section. jThe. casing may be fof. any suitable material, .preferably copper because of its .heat conductivity. In the course of time the resistanceelement in electric heatersfis liableto burn outor to deteriorate, l e.. ,gig f =According toI the present invention; it is made removable and replaceable..` The insuf. lation immediately surrounding; thetwire is made in sections-like Fig..2of comparatively short length. This contributes to.,ea se of manufacture and to strength of the pieces and ease of introduction into the casing.

The casing is best made in standard lengths, each a multiple of one-half the length of one of the blocks, so that one size of blocks may be used for all sizes of radiator. The porcelain and wire cost much less than complete strip heaters of known type, and even the cost ot the casing 4 may be added Serial No. 272,584.

without equaling that of standard strip heaters. l -Each block 3 has a rib 5 extending over about half its length and fitting in a groove 6 constituting the remaining half ofthe length of the opposite block. Longitudinal grooves 7 accommodate the coil 1. Near the ends of each block vl,there are .transverse .grooves 8 and 9 so that near the inner closed end of the casing 4 the-coil can pass continuously from one to the other of the grooves 7 as illustrated, for example, at the left of Figli. 1- v The wire coil 1, as shown in 8, may be a close spiral vor` may bestretched more 'or less to separate the convolutions and thusto provide a greater vor lessvolume of` heat or a given lengthof heater.. f A A. The ends of lthe wire runthrough an insulating block 2 (Fig. 1) which is grooved and engaged by an inward flange-0n acap- 10 whichy is screwed or otherwise removably fastenedomto the end ofthe casing 4.

Then a heatingelement is to be intro,- duced, the center of the= coil is looped through the transverse opening 8 of one of the blocks and laid in thegrooves thereof between said block and a half lengthpiece, such as 3 (Fig. 4). The two blocksa're held togethereand inserted into the open. end of the casing 4.v Additional blocks arethen added at alternate sides, pushing each in turn linto the-casing until the later is full, the last block being another half section like 3a. The length of wire for a desired heat value having been fixed, it maybe stretched to the full lengths of dierent standard casings. Or coils of ldierent lengths, giving diiierent heat values, may be used for-different casings. Such an electric heating element isfa'daptedl to be used as a part of various apparatus or separatelyin electric furnaces, ovens, sol dering irons, curling irons or irons for other uses, immersionI heaters,jspace heaters and thelike.. 'v Where :the standardstrip heaters are made a part of another apparatus, thev burning out o the heater sometimes means the. scrapping of the entire apparatus orv at least the scrap? heating coil Within and to a pair of bladeslsimilar to those on the ordinary vconnection plug, by which the heater connection may be readily made and broken. "",Aceording to Figs. 12 and 13. the porcelain blocks are made interlocking with each other s`o` thatthey may all lbe 'withdrawn simply by pulling out the end one and without putting any strain on the Wire. For this purposeleahblock is providedwith a recess 14 betweenthe two parts 5a and 5l of its projecting rib, and is providedalso with a projectiorifl adapted to 'lit into the recess 14C of its mating block,l as illustrated 'in Fig. 13. Otherwise .these blocks are substantiallylhe an s that of Fiss# 2,13 and, 4:, Ehblk, iskinte'rloel'edwith two blocks on the opposite 's ideas'showninFig.'13.

:ll'Various o'diications 'may beI made by those skilled in the art Without departing from theinvention] as deiined inthe following claims. i f .What Lclaim isz'. 1. An 'electric'heater comprising a casing containing insulating material in the'iorm of removable molded blocks and a resistance elementenclosed thereby, vthe mating blocks being interloclredwith one another in adirec-Y tion'transverse to theline 'of withdrawal tso that the withdrawal of'one causes the vwithnected. at one end by areturn bend passingthrough saidconnecting groove.y

3.. An electric heater comprising a casing, a plurality of rinsulating blocks disposed therein vand a, heater element enclosed by said bloekseach. of said .blocksbeng shaped suhstantially the shape of onehalioifthecasing in cross-section, and having an internally dis-v p Qsed vlongitudinal groove therein, said gfroovesbeing adapted 4to aligny with the grooves ofthe oppositelyfpositioned and the abutting blocks to form 'a passageway forth'e' said heater elenient, said blocks also being adapted to interlock transversely to the longitudinal axis of said blocks one with the other to form a unit assembly removable from said casingyff' "i 4. An electric heater comprising a'casing, a. plurality of insulating blocks disposed therein and a loop shaped heater;elementencl-osed bysaid blocks, each of said bloclrsbeing shapedsubstantially theshape of one half of the casing in cross-section and having a pair of internally disposed longitudinal grooves therein, said grooves being adapted to align with the'grooves of the oppositely positioned and theabutting blocks to form a passageway forthe saidhea-ter element, and each ofsaid blocks having a transverse f groove "connectingsaid longitudinal grofoves dispsedfthe r'eL in with respect to thetransverse grooye of 'an oppositely positioned block to align 'therewith to form a passageway adapted to' receive the loop end 'of said heater element, said blocks also being adapted to interlock transversely tothe lon gitudin'al'axes of s v'aid blocks to form a unit assembly removable from said`casin'g. 5'. 'In' an" 'electric"heaten'ja' plurality 'of molded insulating blocks shaped substan tiallyitothe shape'bf one-"half of thecross section ott-he casingadapted to're'c'eiyeit, each block having an internally'ffdispesed longitudinal 'groove therein'adapted to align with thegrooves in an o1` positely positioned and4 an Jabutting'block to foi-mial passageway therethrough for aheater element," and 4each block being adapted to interlock with its adjacent block to form a unitary assembly re m'ovablefromitseasing.

6; IIn I'an electric' heater, a plurality of molded insulating blocks shaped substantial lyto the shapeof one" half of the cross-'section of the casing adapted to receive it, leach 'block having a pair of internally disposed longitudinal-grooves .therein adapted to align Vwith thegrooves in an oppositely positioned and anfabutti'n'g" block to' form a passageway therethrough'for a' loop shaped heater element'and a transverse groove v'connecting said longitudinal grooves disposed'therein' with respect tothe transverse groove of an oppol sitely 'positioned' block to align vtherewith to ferm' a passageway adapted to receivethe loop end of said heater element and each'block be ing adapted' to interlock' with vitsfadjajcent block to 'form unitary assembly lremovable iro'rii-its'casing.4

' In witness whereof, I have hereunto signed my name.'

-` Y T. BENNETT.

CER'HFIGATE OF CORRECTION.

Patent No. 1,899,933. Marcil 7, 1933.

RVING T. BENNE"T.

'it is hereby certitied that the above numbered patent was erroneously issued to "Thomas E. Murray, of Breokiyn, New York, Joseph Bradley Murray, Thomas E. Murray, Jr., and John F. Murray, Executors of said Thomas E. Murray, deceased", whereas sait Lettere Patent should have been issued to "Metropolitan Engineering Company, n corporation of New York, "as assignee by mesne assignments of the entire interest iu said invention, as shown by the records of assignments in this office; and that the said Letters Patent should be rread with this correction therein that the same may conform to the record of the case in the Patent Office.

Signed and sealed this 9th day of May, A. D. 1933.

M. J. Moore.

(Seal) Acting Commissioner of Patents.

CERTIFCATE OF CORRECTION.

Patent No. 1,899,933. March 7, 1933.

IRVING T. BENNETT.

lt is hereby certified that the above numbered patent was erroneously issued to "Thomas E. Murray, of Brooklyn, New York, Joseph Bradley Murray, Thomas E. Murray, Jr., and John F. Murray, Executors of said Thomas E. Murray, deceased", whereas said 'Letters Patent should have been issued to "Metropolitan Engineering Company, a corporation of New York," as assignee by mesne assignments of the entire interest in said invention, as shown by the records of assignments in this office; and that the said Letters Patent should be kread with this correction therein that the same may conform to the record of the case in the Patent Office.

Signed and sealed this 9th day of May, A. D. 1933.

M. J. Moore.

(Seal) Acting Commissioner oi Patents. 

